Calculator



June 19, 1923. I 1,459,279

w. H. BUTCHER CALCULATOR Filed June v, 1920 V ATTORNEY.

Patented June 19, 1923.

UNITED STATESl PATENT OFFICE.4

CALCULATOR.

Application filed June 7,

4To all whom t may cof/wem:

Be it known that I, WILFRED H. BUTCHER, a citizen of the United States, residing at Burwell, in the county of Garfield and State of Nebraska, have invented certain new and useful Improvements in Calculators, of which the following is a specification.

This invention relates to new and useful improvements in c-alculators, the primary object of the invention beingto provide a device capable of adding and substracting, the invention being particularly adapted for adding a number of purchases and subtracting the amount of the purchases ,from a given amount to determine the amount of change which the purchaser is to receive.

An importantV object of the invention is to provide a 'device of the above nature which includes a pair of movable members and means whereby they may be moved in unison or independently as occasion demands.

Another object of the invention is to provide a calculator including means for mounting a pair of rotatable members whereby they may be rotated in unison or independently, also means for automatically returning the rotatable members to their normal position.

Another object of the invention is to provide a device of the above named character including means for releasably retaining one of the movable members in a set position while the other is being moved to accomplish the desired function.`

' Other objects and advantages of the invention will become apparent during the course of the following description.

In the accompanying drawings forming a part of the application andwherein like numerals are employed to designate-like parts throughout the several figures,

Figure 1 is a front elevation of the calculator, parts thereof being removed.

Figure 2 is a side elevation of the same.

Figure 3 isan enlarged fragmentary seci tion taken through the device, and

Figure 4 is a view illustrating a portion of the engaging faces of the movable member. Y

' Referring to the drawing wherein for the purpose of illustration is shown the preferred embodiment of the invention, the numeral 5 designates a base having mounted thereon a casing 6, the upper forward portion 7 of which is arcuated in the manner 1920. serial No. 387,007.

illustrated most clearly in Figure 2 'and is provided with a sight opening 8 having pointers 9 extending toward the center of the opening lfrom opposite side edges thereof. A pair of movable members constituting a tally wheel 10 and a count wheel 11, are rotatably mounted inl the casing, the count wheel 11 being rotatably mounted upon a shaft 12 extending transversely of the casing, while the tally wheel 10 is keyed thereto. l

' The end of the shaft 12 adjacent the tally wheel 10 is journaled in a bearing plate 13 secured to one side of the casing. The opposite end of the shaft extends through the v count wheel 11 and into a tubular stem 14 for sliding engagement therein. The inner end of the stem is provided with an annular flange `15 which issecured by suitable fastening elements 16 to the hub of' the count wheel 11. The outer end of the stem is journaled through the side of the casing and extended a slight distance therebeyond to bev equipped with a suitable knob or grip 17 whereby the stem and its associated count wheel may be reciprocated upon the shaft 12.

In order to automatically return the count wheels are provided with corresponding numerals and graduations preferably indicating penny, five cent and ten cent marks, each wheel being graduated fromthe zero mark up to $20.00. A clutch means is provided for the two wheels whereby one may be engaged with the other so that both wheels may be rotated in unison, and consists of circumferential clutch teeth 20 provided upon the adjacent faces of the wheels. Normally.` the two wheels are spaced apart and when it is desired to rotate the two wheels in unison inward pressure'is exerted upon the knob 17 of the stem which causes thecount wheel 11 to move inwardly on the shaft 12 until its clutch teeth 20 engage with those of the coacting wheel.

The knob is then turned and thereby ycauses unitary rotation of the two wheels 10 and 11. The tally wheel 10 is retained in any position by pawl and ratchet means, a plurality of peripheral ratchet teeth 21 being provided upon the tally wheel and adapted to cooperate with a spring pressed pawl 22 mounted upon the front of the casing 6, This pawl is urged into engagement with the ratchet teeth 21 by a flat spring 23 which is secured tothe forward end of the casing and exerts inward force uponthe working end of the pawl. The portion of the pawl disposed upon the opposite side of the pivot depends therefrom and is engaged by a push pin 24C slidably mounted through the front of the casing and having a button or knob secured to the exposed end thereof. An abutment 25 is secured .to the push pin and is disposed within the casing to limit downward movement of the push pin caused by thespring 23 urging the pawl into engagement with its ratchet teeth.

From the foregoing description, it will be seen that when itis desired to add severalv items with the` device, the two wheels are positioned so that both register zero. For the purpose of clearness, it will be assumed that the purchaser has purchasedtwo articles costing- 20 and 30e. The clerk exerts an inward pressure upon the knobl 17 to cause the count wheel 11 to move so that its clutch teeth 20 engage the corresponding teeth of the tally wheel 10. During this operation, it is to be borne in mind that thel registers 30e under the pointer 9 therebyl causing the tally wheel to register 50e beneath the pointer. When the wheels are rotated the first time, the spring pressed pawl 22 engages the ratchet teeth 21 and retains the tally wheel in its first position. After the count wheelV has been actuated to register the. second purchase, the tal-ly wheel i-s retained stationary by the pawl 22,

while the count. wheel isA returned by the.

spring 18 to its normal position to register Zero.

Assuming that the purchaser gives the' clerk a $1.00 bill for payment of the purchases, inorder for the clerk to determine the amount of .change to which the pur`V ychaser is entitled,y he again forces the countI wheel into engagement with the tally wheel and turns the knob 17 to cause both wheels to rotate in unison until the tally wheel is rotated sufficiently to bring the $1.00 mark thereof beneath the pointer 9. Then by glancingA at the count wheel, the mark of 50e on the count wheel will be disposed beneath the pointer 9 and will indicate the amount of change to which the purchaser is entitled. After the clerk has completed his calculation, he then presses upon the push pin 24: to release the pawl 22 from engagement with the ratchet teeth 21 which will permit return movement of the tally wheel, the count wheel having been returned by the springv 18 to its normal position.

The foregoing description and' the drawing has reference to the preferred or approved form of my invention.` It is to be understood however that such changes in construction and arrangement of parts, materia-ils, dimensions, jetc., may be made as` prove expedient and fall within the scopeof the appended claims. v

Having thus fully described my inventionV what I claim as new and desire tol secure by Letters Patent is z- 1. A 'calculator comprising spring controlled rotatable count and tally wheels, clutch means between the wheels whereby they may be rotated in' unison, means for releasably retaining the tally wheelsin a set position. and means for causing disengagement o-f the count wheel and independent return movement thereof.

2. A calculator' comprising a easing hav'- ing a sight opening therein, count and tally wheels rotatably mounted in the casing whereby their peripheries are visible through said sight opening, clutch means between the wheels whereby they may rotate in unison,l said wheels also being independently rotatable, springs associated with the wheels for causing their return movement, the spring associated with the count wheel being adapted to'vmove the same laterally of the tally wheel to disengage said clutch means whereby the count wheel may return to its normal. position, ratchet teeth provided on the periphery of the tally wheel, and means `slidably mounted through the casing for association with said ratchet teeth for releasably retaining the tally wheel in iixed relation to the casing.

3. A calculator comprising a casing having a sightopening therein, a shaft extending transversely of the casing, journal'edl at one. end within said casing, a tubular stem mountedy in the side of said casing, and adapted to receive the other end of said transversely extending shaft, av tally wheel keyed to said shaft, a count wheel kmounted on said shaft and connectedto'sai-d tubular stem, spring means carried by said shaft and connected to said tal-ly wheel to' hold the same in anormal position, asecond spring mounted on said tubular stem, the convolutions thereof encircling said stem, one end of said spring being connected t0 said count Wheel and the other end thereof 5 fixed to said easing, clutch means between the wheels whereby they may rotate in unison, said wheels also being independently rotatable, ratohet teeth provided on the periphery of the tally wheel, and means 1U sliclably mounted through the casing for as sooiation with said ratchet teeth for re1eas ably retaining the tally Wheel in fixed relation to the easing.

In testimony whereof I afiX my signature in presence of two witnesses.

WILFRED H. BUICHER.y

Witnesses J AY SGHU'YLER, OLE OLSON. 

